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Distributional patterns and species diversity of benthic insects in an alpine stream in Gunnison County, Colorado, USA were investigated on several levels of spatial scale, from faunal replacement over 1,000 vertical m to microdistribution within the stony substratum. Ecotones including zonation in terrestrial vegetation and in trout distribution did not appear to affect faunal replacement. Competition among congeners accounted for 7-30% of the cases, while in the majority of species, faunal replacement appeared to be associated with gradual changes in the physical gradient. Trout zonation may affect total numbers of insects, however, as the trout-free headwaters had two to six times higher insect densities. Microdistribution...
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This portion of the data release presents fish abundance data from samples collected in the Elwha River estuary, Washington, in 2006, 2007, 2013, and 2014 (no associated USGS Field Activities numbers because data were collected predominantly by biologists from the Lower Elwha Klallam Tribe). We used the Puget Sound beach seining protocol (Simenstad and others, 1991) to sample fish populations in the Elwha River estuary complex. The beach seine was 38 m long x 2 m deep, with a 2 m x 2 m bag in the center of the net; mesh size was 3.18 mm, 6.35 mm, and 31.75 mm, for the bag, center panel, and wings, respectively. The seine net was deployed from bank to bank by a small skiff and then pulled on shore. The number of...
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This portion of the data release presents terrestrial invertebrate abundance data from samples collected in emergent and shrub vegetation along the edge of the Elwha River estuary, Washington, in 2007 and 2013 (no associated USGS Field Activities numbers because data were collected predominantly by biologists from the Lower Elwha Klallam Tribe). We deployed terrestrial insect fallout traps at ten locations in the east estuary, five replicates each in shrub and emergent (littoral) vegetation habitats. Clear, rectangular traps (2,400 cm2 in 2007 and 3,526 cm2 in 2013) were filled with 5 cm of filtered soapy water and deployed for 72 hours. Invertebrate counts from 2013 were standardized to the 2007 bin size to account...
The diversity of forest stands may be affected by landscape fragmentation during periods of climatic change. A modified version of the Image model of the dynamic processes of establishment, growth, and death of forest trees is used in a spatially explicit framework to elucidate differences in the effects of both spatial structure and spatial processes. In cases with and without climatic change, the effects of including random or structured fragmentation and successively lower dispersal probabilities (increased chance of long-distance dispersal) are examined in simulation experiments. The exclusion of very low dispersal probability (p < 0.001) has an important effect on species richness. Barriers and random fragmentation...
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Management of transportation networks is affected by, and has effects on, natural and cultural resources through direct and indirect interactions. Until recently, the availability of such spatially explicit information has been limited; however, the data released here to the public will prove valuable for comparing existing networks and planning options with respect to potential impact to, or from, environmental factors across broad areas, for example, States and Agency Planning Regions. Integrated network and resource analyses can provide insights into potential construction and maintenance costs as well as safety risks and environmental impacts during project planning and assessment. A cooperative project was...
The invasion paradox describes the co-occurrence of independent lines of support for both a negative and a positive relationship between native biodiversity and the invasions of exotic species. The paradox leaves the implications of native?exotic species richness relationships open to debate: Are rich native communities more or less susceptible to invasion by exotic species? We reviewed the considerable observational, experimental, and theoretical evidence describing the paradox and sought generalizations concerning where and why the paradox occurs, its implications for community ecology and assembly processes, and its relevance for restoration, management, and policy associated with species invasions. The crux...
Alien invasions typically reduce species richness of habitats, but few studies have examined their effects on species turnover, the difference in species composition between localities. Agropyron cristatum (L.) Gaertn. (crested wheat grass) has been planted on 6?10 million ha of North American prairie, and is invading native prairie. We studied the invasion of A. cristatum into native prairie by measuring species composition along a gradient from maximum to minimum A. cristatum abundance. As A. cristatum increased, the abundance of most common native species decreased, but one appeared to be unaffected (Bouteloua gracilis (H.B.K.) Lag.), and another (Poa sandbergii Vasey) increased. The effect of A. cristatum on...
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This dataset supports the inclusion of Anodontoides radiatus in the genus Strophitus, introducing the binomial Strophitus radiatus. These data also provide strong support for paraphyly in Strophitus and advocate the resurrection of the genus Pseudodontoides to represent the binomials Pseudodontoides connasaugaensis and Pseudodontoides subvexus.
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This portion of the data release presents aquatic invertebrate abundance data from samples collected in the Elwha River estuary, Washington, in 2007 and 2013 (no associated USGS Field Activities numbers because data were collected predominantly by biologists from the Lower Elwha Klallam Tribe). Replicate benthic samples were collected at 18 locations throughout the estuary complex using a petite Ponar grab sampler (appx. 2400 mL sample) and sorted through a 500-micron sieve. Samples were fixed in 10 percent formalin for 3 to 5 days before being transferred to 70 percent ethanol until processing. Individuals were identified to the lowest possible taxonomic resolution, but are grouped according to insect Orders in...
To define the faunal context within which local and regional resource management decisions are made, conservation of biological diversity requires an understanding of regional species occurrence patterns. Our study focused on the Southern Rocky Mountains of New Mexico and included the San Juan, the Sangre de Cristo, and the Jemez Mountains. Across this region, we quantified patterns of species richness and faunal diversity based on reported and predicted occurrences for birds, mammals, reptiles, amphibians, fish, and butterflies across this region. Specific hypotheses related to the origin and maintenance of observed diversity patterns were tested and interpreted based on their implication for biodiversity assessment...
Semi-arid ecosystems cover tens of millions of hectares in the Intermountain West of the United States, and most have altered plant communities due to land use, especially livestock grazing. Thus, relatively unaltered ?reference? plant community information is needed to guide restoration. Plant communities were sampled over a large (600 000 ha) semi-arid landscape in western Colorado, within pi�on?juniper woodlands, sagebrush shrublands, and grasslands, and over conditions ranging from relict areas without livestock grazing to heavily utilized areas. Ordination was used to group samples into ranked categories of ecological condition within 18 communities, and means?tests and other techniques were used to identify...
We studied the associations of crayfish with reach-scale instream habitat and water quality variables and watershed-scale variables of riparian and watershed land cover, runoff, impervious surfaces, and hydrologic soil type in west-central Indiana. Crayfish assemblage was measured by abundance, species richness, and diversity (Shannon's H) at 180 sites. The western portion of the study area, within the Interior River Lowland ecoregion, has been heavily impacted by agriculture, while the eastern portion, within the Interior Plateau ecoregion, is more heavily wooded and less impacted. The ability of variables at each spatial extent to predict crayfish assemblage was assessed using multiple linear regression analysis....
Categories: Publication; Types: Citation; Tags: ASFA 1: Biological Sciences & Living Resources, Abundance, Agricultural development, Agriculture, Biology--Entomology, All tags...
The productivity of grasslands depends in part on their diversity of species and functional composition. Our objective was to examine the effects of three landscape positions (summit, backslope, and toeslope) and three stocking systems (continuous, rotational, and nongrazed) on species diversity and percentage of cover of grass, legume, and weed species functional types in southeastern Iowa pastures. Data were collected in 0.2-m2 plots randomly distributed throughout each of four replicate pastures in spring and summer 2000 and 2001. Backslope landscape positions within pastures managed with either continuous or rotational stocking contained the greatest overall diversity of species. Across years, overall species...
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These data sets consist of data collected during 2005-2007, 2010, and 2015 at Neal Smith NWR (IA) and Fergus Falls, Litchfield, and Morris Wetland Management Districts (MN) that were used in the analysis in support of the article titled "Integrity of tallgrass prairie reconstructions ten years after planting: native plant persistence and exotic weed resistance," which has been submitted to the journal Restoration Ecology. The primary goal of this study was to understand what influence early reconstruction practices have on long-term outcomes. Twelve replicates of three planting methods (dormant-season broadcast, growing-season broadcast, and growing-season drill) and three seed mix richness levels (10, 20 or 34...
Macroecology is a big-picture, statistical approach to the study of ecology. By focusing on broadly occurring patterns and processes operating at large spatial and temporal scales and ignoring localized and fine-scaled details, macroecology aims to uncover general mechanisms operating at organism, population and ecosystem levels of organization. Although such an approach is evident in writings dating from the mid- to late 1800s, not until 1989 was the domain of macroecology clearly articulated. Since then there has been an exponential growth in publications employing a macroecological perspective. Here we (1) briefly review the history of macroecology, with emphasis on cultural, scientific and technological innovations...
    map background search result map search result map Compilation and Assessment of Resource Values and Hazards to Inform Transportation and Associated Land-use Planning Persistence of native and exotic plants ten years after prairie reconstruction data set Aquatic invertebrate abundance in the Elwha River estuary, Washington, in 2007 and 2013 Fish abundance in the Elwha River estuary, Washington, from 2006 to 2014 Terrestrial invertebrate abundance in the Elwha River estuary, Washington, in 2007 and 2013. Terrestrial invertebrate abundance in the Elwha River estuary, Washington, in 2007 and 2013. Fish abundance in the Elwha River estuary, Washington, from 2006 to 2014 Aquatic invertebrate abundance in the Elwha River estuary, Washington, in 2007 and 2013 Persistence of native and exotic plants ten years after prairie reconstruction data set Compilation and Assessment of Resource Values and Hazards to Inform Transportation and Associated Land-use Planning